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461.
Global scale drivers such as international markets for shrimp can trigger large changes at local and regional scales. But there is also a poorly appreciated reverse process, operating from the bottom up, with potential for triggering changes at higher scales. Thus, effects of drivers can be seen as a two-way process in which global drivers and local and regional drivers can potentially impact each other. Here, we argue that not only can global drivers impact the sustainability of local and regional social-ecological systems, but sustainability at higher scales can also be impacted by changes at the scale of local and regional social-ecological systems. Using Chilika, a large lagoon on the Bay of Bengal, Odisha State in India as a case, we show that traditional small-scale capture fisheries supporting 150 fisher villages with some 400,000 people were marginalized by aquaculture development for tiger prawn and by state-driven hydrological interventions, with impacts on the ecology of the lagoon. These changes, in turn, contribute to global poverty and food insecurity, making it difficult for India to meet international targets such as millennium development goals. The marginalized fisherfolk become part of environmental justice and other social movements. With large parts of the lagoon converted into a virtual monoculture for the production of tiger prawn, changes in Chilika (a Ramsar site) contribute to wetland habitat loss at the global scale, and biodiversity losses, possibly including IUCN red-listed species.  相似文献   
462.
Jatropha curcas L. (Jatropha) is an important multipurpose tree valued for oil. In India, plans are underway to bring substantial area under this crop for meeting the biofuel requirements of the country. A study was conducted to develop allometric relationships in Jatropha to predict various biomass-related components (above ground and below ground) using easily measurable attributes, viz. collar diameter, tree height, number of branches, crown diameter, and crown depth. Further, it was aimed to establish the reliability of these relationships using an independent dataset obtained from varied management situations. Destructive sampling was carried out during the rainy season of 2011, when Jatropha plants were eight years old. Highly significant allometric relationships (F-values significant at 1% level) were obtained while predicting various biomass components (above, below, and total) using easily measurable attributes with R2 values ranging from 0.89 to 0.98. Of all the predictors, collar diameter exhibited a highly significant relationship with total dry biomass per plant (R2 = 0.97). The allometric relationships developed were validated with an independent dataset. The allometric relationships developed would serve as valuable tools for estimating total dry biomass production and carbon sequestration with reasonable accuracy in Jatropha systems, as they are proposed to be taken up in substantial area in the years to come.  相似文献   
463.
Purpose. In ergonomics and human factors investigations, pulling force (PF) estimation has usually been achieved using various types of biomechanical models, and independent approximation of PF was done with the help of upper extremity joints. Recently, multiple regression methods have gained importance for task-relevant inputs in predicting PF. Artificial neural networks (ANNs) also play a vital role in fitting the data; however, their use in work-related biomechanics and ergonomics is inadequate. Therefore, the current research aimed to accomplish comparative investigation of ANN and regression models by assessing their capacity to predict PF values. Methods. Multipositional PF data were acquired from 200 subjects at three different handle heights and body locations. ANN and regression models were formed using a random sample of three subsets (75% training, 15% selection, 10% validation) for proving the outcomes. Results. The comparison of ANN and regression models shows that the predictions of ANN models had a profoundly explained variance and lower root mean square difference values for the PF data at three handle heights. Conclusions. These outcomes advise that ANNs offer a precise and robust substitute for regression methods, and should be considered a useful method in biomechanics and ergonomics task assessments.  相似文献   
464.
Photodegradation of alphacypermethrin ((RS)-alpha cyano-3-phenoxy benzyl (1RS) cis-3-(2,2,dichlorovinyl)-2,2-dimethyl cyclopropane carboxylate) was studied as a thin film on glass surface and on black and red soil surfaces. A number of photoproducts from glass surfaces have been isolated, characterized and identified by gas chromatography-mass spectroscopy (GC-MS). However, only two of them viz. 3-phenoxy benzyl alcohol and [2,2-dichlorovinyl-3(2,2,dimethyl) cyclopropane carboxylate] could be identified from both the soil. Rate of photodegradation on glass and soil surface under UV and sunlight followed first order kinetics with significant correlation coefficients. The rate of photodegradation was greater on black than on red soil.  相似文献   
465.
Environmental Chemistry Letters - Polyethylene terephthalate is a common plastic in many products such as viscose rayon for clothing, and packaging material in the food and beverage industries....  相似文献   
466.
Environmental Chemistry Letters - Global pollution is calling for advanced methods to remove contaminants from water and wastewater, such as TiO2-assisted photocatalysis.  The...  相似文献   
467.
Environmental Science and Pollution Research - Assessment of life history strategies of economically important small indigenous fishes (SIF) which are rich in nutritive values is essential and...  相似文献   
468.
Regional Environmental Change - The Himalayan region is not only threatened by rapid changes in anthropogenic activities but also by global climate change. Given the uncertainties of magnitude and...  相似文献   
469.
470.
The need for environmental and urban planning reached a critical point in the year 2007, when one-half of the world's population could be defined as living in cities. Urbanisation in India is also increasing at a fast rate. Urban chaos in India, emanating from the continuous ignorance of fragile ecosystems, calls for the reshaping of existing cities as ‘eco-cities’. The ‘eco-city’—a well-known concept in the western world—is new to the Indian context. While western connotations of eco-cities should not be discarded outright in the context of India, core concerns vary significantly for obvious reasons. Recognising two facts—firstly, eco-city development is altogether a fresh approach to human settlement development in India, and, secondly, the manifold increase in the vulnerability of cities—this paper discusses documented good practice, reinforcing evolution towards the eco-city vision. Lessons drawn from the examples cited are further deconstructed in the light of their contribution to urban risk reduction, which provides direction to appreciating the ‘disaster-resilient eco-community’ concept in Puri, a coastal city in India. Further, this paper attempts to unravel existing community-based practices in Puri, which are boon to the local environment and invariably reduce disaster risk. These seemingly modest neighbourhood initiatives symbolise immense societal wealth, which can be calibrated appropriately for reducing urban environmental risk as well. This paper also illustrates how a ‘disaster resilient eco-community’ approach is inevitable in the present and future contexts not only to preserve sustainable development gains but also to secure human well-being.  相似文献   
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